In order to provide core support for the research projects, the Program Project Grant has four Core units, i.e., an Administrative Core (P.I.; D.N.Granger), a Cell Culture Core (P.I.; P.R Kvietys), a Biochemistry Core (P/I/; M.B. Grisham), and a Morphology Core (P.I.; R. Specian). These Cores will provide shared facilities and resources for the investigators in the PPG and play an important role in enhancing the interaction among investigators. The primary functions of the Administrative Core are to co- ordinate the activities of the component Projects and Cores, to manage purchasing and budgetary matters, to provide secretarial support for the various Projects and Cores, and to schedule meetings and seminars in the PPG. The cell Culture Core will provide cultured endothelial and epithelial cells for specific Projects in the PPG. The Biochemistry Core will perform various spectrophotometric and fluorometric assays, protein separation and purification, and enzyme inactivation procedures for several projects. The Morphology Core will provide facilities and expertise for light and electron microscopic studies of the mucosal membrane, blood vessels, leukocytes, and cultured endothelial cells. The four Core units will provide an efficient means for generating the services needed to conduct the proposed research and to attain the stated goals of the Program.